Summary Glenohumeral arthritis, or Shoulder Arthritis, is a degenerative joint disease of the shoulder characterized by damage to the articular surfaces of the humeral head and/or glenoid. Diagnosis is made radiographically with true AP shoulder ("Grashey") and axillary lateral radiographs. Treatment is observation, NSAIDs, and corticosteroids for minimally symptomatic patients. Shoulder arthroplasty is indicated for progressive symptoms with severe degenerative disease. Epidemiology Incidence increases with age more likely in patients over 60 Demographics more common in women Risk factors 56% of patients who had primary anterior dislocation have arthrosis at 25 years follow up Etiology Causes primary osteoarthritis secondary arthritis post-traumatic arthritis of dislocation inflammatory/crystalline arthritis osteonecrosis neuropathic (Charcot Arthropathy) rotator cuff arthropathy Pathophysiology primary osteoarthritis articular cartilage login to view 1 more bullet humeral head login to view 1 more bullet glenoid login to view 2 more bullets rotator cuff login to view 1 more bullet post-traumatic arthritis articular surface incongruities following trauma healing can lead to joint deterioration commonly occurs in patients with humeral fractures and chronic dislocations cuff tear arthropathy torn rotator cuff tendons leads to humeral head migration and subsequent abrasive contact between the humeral head and acromion which leads to articular wear dislocation arthropathy repeated dislocation can cause erosion of joint cartilage higher incidence with login to view 4 more bullets post-capsulorraphy arthropathy excessive tightening of soft tissues in stabilization surgeries to treat recurrent dislocation forces humeral head in one direction login to view 1 more bullet inflammatory/crystalline arthritis rheumatoid arthritis login to view 4 more bullets calcium pyrophosphate dihydrate deposition disease (CPPD) login to view 1 more bullet gout login to view 1 more bullet osteonecrosis/avascular necrosis bone cell death caused by interruption of blood supply to humeral head leads to subchondral bone collapse and morphological/arthritic changes causes login to view 12 more bullets chondrolysis occurs following shoulder arthroscopy exact pathophysiology unknow but associated with login to view 4 more bullets leads to the dissolution of articular cartilage has less osteophytes than OA Associated conditions rotator cuff tears 5-10% incidence with OA 25-50% incidence with RA Anatomy Glenohumeral (GH) joint joint comprised of humeral head and glenoid fossa of scapula stability static restraints login to view 2 more bullets dynamic restraints login to view 3 more bullets Glenoid osteology glenoid is 3 degreees retroverted humerus is 20-30 degrees retroverted Classification Walch Classification of Glenoid Wear Type A Concentric wear, no subluxation of HH, well centered A1: no or minor central erosion A2: deeper central erosion, line connects anterior/posterior glenoid rims and transects humeral head (HH) Type B Biconcave glenoid, asymmetric glenoid wear and head subluxated posteriorly B0: pre-osteoarthritic posterior subluxation of HH B1: posterior joint narrowing (no posterior bone loss), osteophytes, subchondral sclerosis B2: posterior rim erosion, retroverted glenoid B3: mono-concave, posterior wear, at least HH subluxation >70% OR retroversion >15 degrees Type C C1: Glenoid retroversion >25 degrees, regardless of erosion C2: Biconcave, posterior bone loss, posterior translation of HH Two main subtypes of dysplastic glenoids have been observed ("Lazy J" and "Delta") Type D Glenoid anteversion or anterior HH subluxation (HH subluxation <40%) Presentation Symptoms shoulder pain worse with activities involving shoulder motion often no pain at rest loss of range of motion especially external rotation due to anterior capsule contraction difficulty sleeping Physical exam functional limitations at glenohumeral joint decreased external rotation, forward flexion, and internal rotation variable and more active patients have better range of motion (ROM) crepitus catching/squeaking with articulation motor a carefully evaluation of the rotator cuff muscles should be performed Functional Outcomes Scores ASES Shoulder Score Constant Score Oxford Shoulder Score Imaging Radiographs recommended views true anteroposterior (AP) of GH joint AP axillary lateral findings often diagnose etiology primary osteoarthritis login to view 5 more bullets post-traumatic arthritis login to view 2 more bullets arthritis of dislocation login to view 2 more bullets inflammatory/crystalline arthritis login to view 12 more bullets osteonecrosis/avascular necrosis login to view 4 more bullets rotator cuff tear arthropathy login to view 6 more bullets Computed tomography (CT) indications evaluate glenoid morphology and rotator cuff pathology for pre-operative planning may underestimate full-thickness RCTs and fatty infiltration/muscle atrophy compared to MRI allows for pre-operative templating Magnetic Resonance Imaging (MRI) indications evaluate rotator cuff pathology for pre-operative planning less accurate than CT in distinguishing between glenoid types Treatment Nonoperative physical therapy, NSAIDs indications login to view 1 more bullet modalities login to view 2 more bullets intraarticular Injections indications login to view 1 more bullet modality login to view 3 more bullets DMARDs indications login to view 1 more bullet Operative total shoulder arthroplasty (TSA) indications login to view 4 more bullets contraindications login to view 3 more bullets technique login to view 1 more bullet outcomes login to view 5 more bullets hemiarthroplasty indications login to view 3 more bullets technique login to view 4 more bullets outcomes login to view 2 more bullets reverse shoulder arthroplasty (RSA) indications login to view 6 more bullets technique login to view 1 more bullet outcomes login to view 3 more bullets arthroscopic debridement indications login to view 3 more bullets outcomes login to view 4 more bullets CAM (comprehensive arthroscopic management) procedure indications login to view 1 more bullet technique login to view 1 more bullet arthrodesis indications login to view 5 more bullets outcomes login to view 2 more bullets Techniques Total shoulder arthroplasty Hemiarthroplasty Reverse ball prosthesis